Tuesday, November 02, 2010

Medical History: Diagnosing with Yarn

Today, I depart from the usual tediously detailed ramblings on knitting to bring you a little story about how colored yarn was used in early research into color blindness. Interesting, no?

I'm currently reading Through the Language Glass: Why the World Looks Different in Other Languages, by Guy Deutscher. It's quite good so far. In the early part of the book, there is a section about how the vocabulary of color arose (or didn't) in various languages and what that might have to say about cultural development. As it happens, at the same time that linguists were talking about color vocabulary, the concept of color-blindness was recognized.

And an early tool in the diagnosing of color blindness was something called the Holmgren Test for Color Blindness. Devised by Swedish professor Alarik Holmgren after a horrible color-blindness-related train crash, this test was used to determine color blindness in employees of occupations related to public transportation and shipping and other trades where being able to discern color accurately was of great importance. This tool was also used in cultural anthropology research to test the detail of color vocabulary amongst various groups -- for instance, noting whether a language discriminated between blue and black, for instance.

In the color-blindness application, those being tested were asked to choose from among the available scraps of yarn for the 10 pieces that best matched, say, a light green. Clicking on the image above will take you to the web site for the the UK's Science Museum's website on the history of medicine. From there, clicking on the image takes you to a very large version where you can read the tester's instructions inside the lid of the box. I think it's cool that some of these original 19th-century kits have been preserved -- and that the pieces of wool inside are still so vibrant -- assuming those are still the originals.

Thus endeth the lesson.


  1. Cool! We have a lot of yarn in our house, and a colorblind boy. I think I'll play yarn games with him...

  2. That is really interesting. We talk about color blindness all the time since we have a red-green blind boy at home.

  3. That's very cool! I only knew about the Ishihara plates to test for color blindness - didn't know you could use yarn!